280 AGRONOMY 



that the weedy, prickly lettuce of waste places and neglected 

 gardens is the same species as the tender, smooth-leaved, solid- 

 headed plant so highly valued in cultivation. The lettuce 

 was once grown for its loose leaves, which were little changed 

 from the original, but nowadays it has been bred to make solid 

 heads like a cabbage. The spinach, which much resembles the 

 lettuce in form, has been known since earliest times. It is a 

 native of Persia. The onion is another species valued for its 

 edible leaves, though many think the bulbous part is a root. 

 It is, however, a true bulb made up of the thickened bases of 

 the leaves. The cultivated onion is a native of western Asia 

 and has been known for centuries. Many other species grow 

 wild in both Europe and America. The leek is a species of 

 onion and grows wild on both sides of the Atlantic. Celery 

 has long been in cultivation, but may still be found wild in 

 parts of Europe and western Asia. It belongs to the same 

 plant family as the parsley, parsnip, carrot, fennel, dill, corian- 

 der, and other species valued for their aromatic seeds. Aspara- 

 gus, though not a leaf crop, may be mentioned in this connec- 

 tion. It has been cultivated for many centuries, and is, of 

 course, a native of the Old World. In the wild state the 

 stems of asparagus are rather slender, but under proper cul- 

 tivation they reach a diameter of more than an inch. 



The legumes. Some species of legumes seem to have been 

 among the first plants cultivated by man. The seeds of peas 

 and lentils have been found among materials referred to the 

 Bronze Age of Europe. The word " legume " comes from the 

 Latin legere, meaning " to gather," and seems originally to 

 have been applied to any species of plant gathered by hand. 

 The seeds of the plants now called legumes were usually prom- 

 inent in such gathered crops, and the name has since come to 

 be restricted to them. The lentil, little grown in America, has 

 long been cultivated in the warmer parts of the Old World, 

 especially in the Mediterranean region, and the pea has 



